This invention relates to the orthodontic field and particularly relates to the removal of brackets secured to the teeth by a process known as "bonding".
The practice of orthodontia includes the securing of brackets to teeth by bonding, usually with cement. Orthodontists use these brackets to carry straightening wires. The securing of these brackets, which may be of metal or plastic and which are attached by cement, is an improvement in the resulting attachment of the brackets to the face of the tooth. Although the adhesion of the cement to the tooth surface is quite good, the removal of these brackets by conventional tools is extremely difficult due to the adhesion of the cement to the tooth.
There are several tools described in the patent literature which address the problem of removing these brackets from teeth. Among these are Northcutt U.S. Pat. No. 3,755,902 which utilizes a pliers-type tool in which a chisel edge cleaves the onlay from the tooth and the other jaw of the pliers bears against the biting edge of the tooth. Cusato U.S. Pat. No. 3,986,265 also utilizes a pliers-type tool with chisel edges on both jaws to pry the brackets from the tooth. Cusato also utilizes a plastic cover which fits over one jaw so that this jaw can be engaged with the biting edge of the tooth and the chisel edge on the other jaw used to scrape cement from the tooth. Hoffman U.S. Pat. No. 3,911,583 shows a pliers-type instrument for removing bands and cement from a tooth. Hoffman utilizes one jaw or beak as a pivot or fulcrum against the occlusal surface of the tooth and the other jaw or beak has a scaping edge to remove the bracket or cement from the tooth. Kurz U.S. Pat. No. 4,248,587 describes a variety of orthodontic tools for removing brackets from teeth with one of the jaws having means for engaging the top of the tooth while the device is being used. Kricker U.S. Pat. No. 326,909 and Manuel U.S. Pat. No. 4,189,839 show tools with bifurcated jaws, while Shiner U.S. Pat. No. 2,985,962 and Angle U.S. Pat. No. 1,299,103 show tools for removing bands from around the tooth. There also is commercially available a tool in which a wire is hooked to a wing of a bracket and is pulled against a pair of legs which bear against the tooth. This device is effective only in certain areas of the mouth.
Many of the known tools have the impediment that they tend to impart a twisting or bending motion to the tooth, to the discomfort of the patient and sometimes result in damage to the tooth.
Accordingly, it is a principal object of this invention to provide an orthodontic tool for removing brackets cemented to the surface of the tooth.
Another object of this invention is to provide a bracket remover having a pliers-like structure with bifurcated lower jaw for engaging the tooth surface to which the bracket is cemented and a second jaw shaped to engage the bracket, whereby when the jaws are separated, sufficient force is generated to break the cement bond and free the bracket from the tooth.
Still another object is to provide a tool which can be used to remove both wing and Begg type brackets utilizing a lower beak which straddles the bracket and bears against the tooth surface to which the bracket is attached and an upper beak which engages the bracket and acts against the lower jaw to urge the bracket away from the tooth.
Still a further object of this invention is to provide an instrument having a bifurcated lower jaw for straddling a bracket and for engaging the tooth to which the bracket is cemented and an offset upper jaw for engaging a wing on one side of the bracket and for urging the bracket away from the tooth when the jaws are separated.
Still another object is to provide an instrument having offset upper and lower beaks for operating in confined small areas whereby one beak engages the surface of a tooth to which a bracket is fastened and the other beak engages a wing on the bracket to disengage the bracket from the tooth when the beaks are separated.
These and other objects and advantages will become apparent hereinafter.